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color of a zone-shaped region whose surface is many times greater than the whole surface of our earth? It is true that a brief change might be readily explained as due to such changes as occur in our own air. Large regions of the earth are at one time cloud-covered and at another free from clouds. Such regions, seen from Venus or Mercury, would at one time appear white, and at the other would show whatever color the actual surface of the ground might possess when viewed as a whole. But it seems altogether impossible to explain in this way a change or series of changes occupying many years, as in the case of the recent color-changes of Jupiter's belt. Let me not be misunderstood. I am not urging that the changes in Jupiter are not due to the formation and dissipation of clouds in his atmosphere. On the contrary, I believe that they are. What seems to me incredible, is the supposition that we have here to deal with such changes as occur in our own air in consequence of solar action.

I do not lose sight of the fact that the Jovian year is of long duration, and that whatever changes take place in the atmosphere of Jupiter through solar action might be expected to be exceedingly slow. Nay, it is one of the strongest arguments against the theory that solar action is chiefly in question, that any solar changes would be so slight as to be in effect scarcely perceptible. It is not commonly insisted upon in our text-books of astronomy -in fact, I have never seen the point properly noticed anywhere-that the seasonal changes in Jupiter correspond to no greater relative change than occurs in our daily supply of solar heat from about eight days before to about eight days after the spring or autumn equinox. It is incredible that so slight an effect as this should produce those amazing changes in the condition of the Jovian atmosphere which have unquestionably been indicated by the varying aspect of the equatorial zone. It is manifest that, on the one hand, the seasonal changes should be slow and slight so far as they depend on the sun, and, on the other, that the sun cannot rule so absolutely over the Jovian atmosphere as to cause any particular atmospheric condition to prevail unchanged for years.

If, however, Jupiter's whole mass is in a state of intense heat-if the heat is in fact sufficient, as it must be, to maintain an effective resistance against the tremendous

force of Jovian gravitation-we can understand any changes, however amazing. We can see how enormous quantities of vapor must continually be generated in the lower regions to be condensed in the upper regions, either directly above the zone in which they were generated, or north or south of it, according to the prevailing motions in the Jovian atmosphere. And although we may not be able to indicate the precise reason why at one time the mid-zone or any other belt of Jupiter's surface should exhibit that whiteness which indicates the presence of clouds, and at another should show a coloring which appears to indicate that the glowing mass below is partly disclosed, we remember that the difficulty corresponds in character to that which is presented by the phenomena of solar spots. We cannot tell why sun-spots should wax and wane in frequency during a period of about eleven years; but this does not prevent us from adopting such opinions as to the condition of the sun's glowing photosphere as are suggested by the behavior of the spots.

It may be asked whether I regard the ruddy glow of Jupiter's equatorial zone, during the period of disturbance lately passed through, as due to the inherent light of glowing matter underneath his deep and cloud-laden atmosphere. This appears to me on the whole the most probable hypothesis, though it is by no means certain that the ruddy color may not be due to the actual constitution of the planet's vaporous atmosphere. In either case, be it noted, we should perceive in this ruddy light the inherent lustre of Jupiter's glowing mass, only in one case we assume that that lustre is itself ruddy, in the other we suppose that light, originally white, shines through ruddy vapor-masses. It is to be remembered, however, that whichever view we adopt, we must assume that a considerable portion of the light received, even from these portions of the planet's disc, must have been reflected sunlight. In fact, from what we know about the actual quantity of light received from Jupiter, we may be quite certain that no very large portion of that light is inherent. Jupiter shines about as brightly as if he were a giant cumulus-cloud, and therefore almost as white as driven snow. Thus he sends us much more light than a globe of equal size of sandstone, or granite, or any known kind of earth. We get from him about three times as much light as a globe like

our moon in substance, but as large as Jupiter, and placed where Jupiter is, would reflect towards the earth; but not quite so much as we should receive from a globe of pure snow of the same size and similarly placed. It is only because large parts of the surface of Jupiter are manifestly not white, that we seem compelled to assume that some portion of his light is inherent. But the theory that Jupiter is intensely hot by no means requires, as some mistakenly imagine, that he should give out a large proportion of light. His real solid or liquid globe (if he have any) might, for instance, be at a white heat, and yet so completely cloud-enwrapped that none of its light could reach us. Or, again, his real surface might be like red-hot iron, giving out much heat but very little light.

I shall close the present statement of evidence in favor of what I begin to regard as in effect a demonstrated theory, with the account of certain appearances which have been presented by Jupiter's fourth satellite during recent transits across the face of the planet. The appearances referred to have been observed by several telescopists, but I will select an account given in the monthly notices of the "Astronomical Society," by Mr. Roberts, F.R.A.S., who observed the planet with a fine telescope by Wray, 8 inches in aperture. "On March 26, 1873," he says, "I observed Jupiter about 8 p.m., and found the fourth satellite on the disc. I thought at first it must be a shadow; but, on referring to the 'Nautical Almanac,' found that it was the fourth satellite itself. A friend was observing with me, and we both agreed that it was a very intense black, and also was not quite round. We each made independent drawings which agreed perfectly, and consider that the observation was a perfectly reliable one. We could not imagine that such an intensely black object would be visible when off the disc, and waited with some impatience to see the emersion, but were disappointed by fog, which came on just at the critical time." Another observer, using a telescope only two inches in aperture, saw the satellite when off the disc, so that manifestly the blackness was merely an effect of contrast.

In considering this remarkable phenomenon, we must not forget that the other satellites do not look black (though some of them look dark) when crossing Jupiter's disc, so that we have to deal with a circumstance peculiar to the fourth or outer

most satellite. Nevertheless, we seem precluded from supposing that any other difference exists between this satellite and the others than a certain inferiority of light-reflecting power. I might indeed find an argument for the view which I have suggested as not improbable, that Jupiter is a heat-sun to his satellites, since the three innermost would be in that case much better warmed than the outermost, and therefore would be much more likely to be cloud-encompassed, and so would reflect more light. But I place no great reliance on reasoning so ingenious, which stands. much as a pyramid would stand (theoretically) on its apex. The broad fact that a body like the fourth satellite, probably comparable to our moon in light-reflecting power, looks perfectly black when on the middle of Jupiter's disc, is that on which I place reliance. This manifestly indicates a remarkable difference between the brightness of Jupiter and the satellite; and it is clear that the excess of Jupiter's brightness s in accordance with the theory that he shines in part with native light, or, in other words, is intensely heated.

This completes the statement of the evidence obtained during the recent opposition of Jupiter in favor of a theory which already had the great advantage of according with all known facts, and accounting for some which had hitherto seemed inexplicable. If this theory removes Jupiter from the position assigned to him by Brewster as the noblest of inhabited worlds, it indicates for him a higher position as a subordinate sun, nourishing with his heat, as he sways by his attractive energy, the scheme of worlds which circles round him. The theory removes also the difficulty suggested by the apparent uselessness of the Jovian satellites in the scheme of creation. When, instead of considering their small power of supplying Jupiter with light, we consider the power which, owing to his great size and proximity, he must possess of illuminating them with reflected light, and warming them with his native heat, we find a harmony and beauty in the Jovian system which before had been wanting; nor, when we consider the office which the Sun subserves towards the members of his family, need we reject this view on account of the supposition

That bodies bright and greater should not serve

The less not bright.

-Popular Science Review.

color of a zone-shaped region whose surface is many times greater than the whole surface of our earth? It is true that a brief change might be readily explained as due to such changes as occur in our own air. Large regions of the earth are at one time cloud-covered and at another free from clouds. Such regions, seen from Venus or Mercury, would at one time appear white, and at the other would show whatever color the actual surface of the ground might possess when viewed as a whole. But it seems altogether impossible to explain in this way a change or series of changes occupying many years, as in the case of the recent color-changes of Jupiter's belt. Let me not be misunderstood. I am not urging that the changes in Jupiter are not due to the formation and dissipation of clouds in his atmosphere. On the contrary, I believe that they are. What seems to me incredible, is the supposition that we have here to deal with such changes as occur in our own air in consequence of solar action.

I do not lose sight of the fact that the Jovian year is of long duration, and that whatever changes take place in the atmosphere of Jupiter through solar action might be expected to be exceedingly slow. Nay, it is one of the strongest arguments against the theory that solar action is chiefly in question, that any solar changes would be so slight as to be in effect scarcely perceptible. It is not commonly insisted upon in our text-books of astronomy -in fact, I have never seen the point properly noticed anywhere-that the seasonal changes in Jupiter correspond to no greater relative change than occurs in our daily supply of solar heat from about eight days before to about eight days after the spring or autumn equinox. It is incredible that so slight an effect as this should produce those amazing changes in the condition of the Jovian atmosphere which have unquestionably been indicated by the varying aspect of the equatorial zone. It is manifest that, on the one hand, the seasonal changes should be slow and slight so far as they depend on the sun, and, on the other, that the sun cannot rule so absolutely over the Jovian atmosphere as to cause any particular atmospheric condition to prevail unchanged for years.

If, however, Jupiter's whole mass is in a state of intense heat-if the heat is in fact sufficient, as it must be, to maintain an effective resistance against the tremendous

force of Jovian gravitation-we can understand any changes, however amazing. We can see how enormous quantities of vapor must continually be generated in the lower regions to be condensed in the upper regions, either directly above the zone in which they were generated, or north or south of it, according to the prevailing motions in the Jovian atmosphere. And although we may not be able to indicate the precise reason why at one time the mid-zone or any other belt of Jupiter's surface should exhibit that whiteness which indicates the presence of clouds, and at another should show a coloring which appears to indicate that the glowing mass below is partly disclosed, we remember that the difficulty corresponds in character to that which is presented by the phenomena of solar spots. We cannot tell why sun-spots should wax and wane in frequency during a period of about eleven years; but this does not prevent us from adopting such opinions as to the condition of the sun's glowing photosphere as are suggested by the behavior of the spots.

It may be asked whether I regard the ruddy glow of Jupiter's equatorial zone, during the period of disturbance lately passed through, as due to the inherent light of glowing matter underneath his deep and cloud-laden atmosphere. This appears to me on the whole the most probable hypothesis, though it is by no means certain that the ruddy color may not be due to the actual constitution of the planet's vaporous atmosphere. In either case, be it noted, we should perceive in this ruddy light the inherent lustre of Jupiter's glowing mass, only in one case we assume that that lustre is itself ruddy, in the other we suppose that light, originally white, shines through ruddy vapor-masses. It is to be remembered, however, that whichever view we adopt, we must assume that a considerable portion of the light received, even from these portions of the planet's disc, must have been reflected sunlight. In fact, from what we know about the actual quantity of light received from Jupiter, we may be quite certain that no very large portion of that light is inherent. Jupiter shines about as brightly as if he were a giant cumulus-cloud, and therefore almost as white as driven snow. Thus he sends us much more light than a globe of equal size of sandstone, or granite, or any known kind of earth. We get from him about three times as much light as a globe like

our moon in substance, but as large as Jupiter, and placed where Jupiter is, would reflect towards the earth; but not quite so much as we should receive from a globe of pure snow of the same size and similarly placed. It is only because large parts of the surface of Jupiter are manifestly not white, that we seem compelled to assume that some portion of his light is inherent. But the theory that Jupiter is intensely hot by no means requires, as some mistakenly imagine, that he should give out a large proportion of light. His real solid or liquid globe (if he have any) might, for instance, be at a white heat, and yet so completely cloud-enwrapped that none of its light could reach us. Or, again, his real surface might be like red-hot iron, giving out much heat but very little light.

I shall close the present statement of evidence in favor of what I begin to regard as in effect a demonstrated theory, with the account of certain appearances which have been presented by Jupiter's fourth satellite during recent transits across the face of the planet. The appearances referred to have been observed by several telescopists, but I will select an account given in the monthly notices of the " Astronomical Society," by Mr. Roberts, F.R.A.S., who observed the planet with a fine telescope by Wray, 8 inches in aperture. "On March 26, 1873," he says, " I observed Jupiter about 8 p.m., and found the fourth satellite on the disc. I thought at first it must be a shadow; but, on referring to the 'Nautical Almanac,' found that it was the fourth satellite itself. A friend was observing with me, and we both agreed that it was a very intense black, and also was not quite round. We each made independent drawings which agreed perfectly, and consider that the observation was a perfectly reliable one. We could not imagine that such an intensely black object would be visible when off the disc, and waited with some impatience to see the emersion, but were disappointed by fog, which came on just at the critical time." Another observer, using a telescope only two inches in aperture, saw the satellite when off the disc, so that manifestly the blackness was merely an effect of contrast.

In considering this remarkable phenomenon, we must not forget that the other satellites do not look black (though some of them look dark) when crossing Jupiter's disc, so that we have to deal with a circumstance peculiar to the fourth or outer

most satellite. Nevertheless, we seem pre-
cluded from supposing that any other dif-
ference exists between this satellite and the
others than a certain inferiority of light-re-
flecting power. I might indeed find an.
argument for the view which I have sug-
gested as not improbable, that Jupiter is a
heat-sun to his satellites, since the three
innermost would be in that case much
better warmed than the outermost, and
therefore would be much more likely to be
cloud-encompassed, and so would reflect
more light. But I place no great reliance
on reasoning so ingenious, which stands
much as a pyramid would stand (theoreti-
cally) on its apex. The broad fact that a
body like the fourth satellite, probably
comparable to our moon in light-reflecting
power, looks perfectly black when on the
middle of Jupiter's disc, is that on which I
place reliance. This manifestly indicates
a remarkable difference between the bright-
ness of Jupiter and the satellite; and it is
clear that the excess of Jupiter's brightness
s in accordance with the theory that he
shines in part with native light, or, in other
words, is intensely heated.

This completes the statement of the evidence obtained during the recent opposition of Jupiter in favor of a theory which already had the great advantage of according with all known facts, and accounting for some which had hitherto seemed inexplicable. If this theory removes Jupiter from the position assigned to him by Brewster as the noblest of inhabited worlds, it indicates for him a higher position as a subordinate sun, nourishing with his heat, as he sways by his attractive energy, the scheme of worlds which circles round him. The theory removes also the difficulty suggested by the apparent uselessness of the Jovian satellites in the scheme of creation. When, instead of considering their small power of supplying Jupiter with light, we consider the power which, owing to his great size and proximity, he must possess of illuminating them with reflected light, and warming them with his native heat, we find a harmony and beauty in the Jovian system which before had been wanting; nor, when we consider the office which the Sun subserves towards the members of his family, need we reject this view on account of the supposition

That bodies bright and greater should not serve
The less not bright.

-Popular Science Review.

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TRANSLATED FROM THE RUSSIAN FOR THE ECLECTIC BY MISS SOPHIE MICHELL.

XXIII.

66

O happy years
And joyful days!
Like floods in spring
Ye've passed away!"

HE continued sleeping soundly for several hours; and, while lying in a doze, he dreamt that he was again fighting a duel, and the adversary standing opposite to him was no other than Herr Klüber; while, perched on a fir-tree close by, was a parrot, and this parrot was old Pantaleone, who kept incessantly repeating, "One, one, one! one, one, one!"

one

one!" that

"One was at last too distinct to be a dream. He opened his eyes, raised his head from his pillow; surely some one had been knocking at his door.

"Come in!" he cried.

The waiter entered, and announced that a lady was outside anxious to see him.

"Gemma!" was the first thought that struck him; but the lady proved to be her mother, Frau Lenore.

No sooner had the latter entered the room than, dropping into a chair, she burst into a flood of tears.

"My dear, good Madame Roselli, what is the matter with you ?" he exclaimed, seating himself next to her, and taking her gently by the hand. "Has any thing happened? Pray calm yourself."

66

"O Herr Dimitri! I am very unhappy." "You unhappy?" "Oh! very. And could I ever have expected this? It has come upon me like a sudden thunderbolt from heaven!" The old lady was breathing with difficulty.

"But what is it? Explain yourself. Will you have a glass of water ?"

"Oh no, thank you." Frau Lenore put her handkerchief up to her eyes, and commenced sobbing again. "I know it all, all !"

"What do you mean by all?"

"All that happened yesterday! And I know the cause of it all! You have acted

like an honorable man; but what an unfortunate string of events! I was right in disapproving of that trip to Soden. You see I was right!" (Frau Lenore had never expressed such disapproval, but she now labored under the delusion that she had felt a presentiment of this "all" even then.) 'I come to you now as to an honorable man, as to a friend, although I have only known you for five days. But I am a widow, an unprotected widow. My daughter.

Here the old lady sobbed afresh. Sanin was at a loss what to think. "Your daughter!" he repeated.

66

'My daughter Gemma," said Frau Lenore, with a groan from beneath her tear-stained handkerchief, "informed me yesterday that she had no wish to marry Herr Klüber, and desired I would refuse him!"

Sanin gave an involuntary start; he had not expected such an announcement.

"I do not mean to say," continued Frau Lenore, "that it is a disgrace, or that such things are not of common occurrence in the world; but it is ruination to us, Herr Dimitri !" Here she nervously twisted her handkerchief into the tiniest ball, as though she wished she could have centred all her sorrow in it. "Our income is not sufficient to keep us, Herr Dimitri, and Herr Klüber is very rich, and will be still richer in time. And why should she refuse him? Because he was not energetic in her defense ? Allowing even that he should have behaved differently, he, you know, is a civilian, and has not received a university education; and, as a solid, matter-offact tradesman, he had only to treat the thoughtless pranks of the young officer with the greatest contempt. But, after all, what great offence was it, Herr Dimitri ?" Pardon me, Frau Lenore, but you seem inclined to condemn me.”

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"No, I do not condemn you in the

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